Tomato/capsicum bacterium update

24 June 2008

New Disease in Plants

MAFBNZ has been working to establish a science based approach to the new species of Liberibacter which was recently discovered in glasshouse tomato and capsicum crops. While it will take time to establish some basic facts we are aware of the need for urgency in getting answers for growers and exporters.

This is the first in a series of regular updates- we will share progress through this forum as information becomes available. Please also check MAFBNZ and HortNZ websites for other information details.

Exports

MAFBNZ has received acknowledgement of New Zealand’s notification of the suspension of export certification for tomatoes and capsicums from fourteen countries. Several importing countries expressed no immediate concerns and were prepared to await further information regarding symptoms, transmission and hosts from New Zealand while export certification is suspended. The United States of America also requested diagnostic protocols with a view to future testing for the bacterium.

Australia has amended their import conditions database to prohibit the importation of nursery stock and the fruit of tomatoes and cherry tomatoes (Lycopersicon esculentum), capsicum (capsicum annuum), chilli (Capsicum frutescens), eggplant (Solanum melongena), pear melon (Solanum muricatum), tamarillo, (Solanum betaceum Syn. Cyphomandra betacea ), tomatillos, ( Physalis ixocarpa) cape gooseberries (Physalis peruviana) and potato (Solanum tuberosum)(prohibited prior to the Liberibacter finding).

The bacterium does not affect citrus and consequently no restrictions have been placed on citrus exports.

The importation of potatoes into Tahiti is still permitted but, as an interim measure, additional import requirements have been put in place. For further information refer to Importing Country Phytosanitary requirements for French Polynesia (http://www.biosecurity.govt.nz/commercial-exports/plant-exports/icpr-register (offsite link to www.biosecurity.govt.nz)).

The major focus for the exports team is re-opening our export markets based on a sound understanding of the risks posed by Liberibacter. An accelerated science programme is in place to assess these risks and will provide a scientific basis for discussions with trading partners on what measures, if any, are technically justified.

Export Compliance Programme

MAFBNZ are working with Horticulture New Zealand to develop a temporary compliance programme for production site freedom, from this bacterium, for glasshouse tomatoes and capsicums. This is being finalised now and should be available for growers and their IVA's to begin using this programme shortly.

Senior MAFBNZ staff will be attending a meeting in Tokyo later this week and, as part of that meeting, will discuss the bacterium find with Japanese officials with a view to developing a process which would allow market access there for tomatoes and capsicums to resume soon as possible.

Science programme

We have already identified a number of key questions which need to be urgently addressed by a research programme. Investigations are already underway to establish -

  • How is the bacterium transmitted?

This will involve investigating potential insect vectors and in particular the tomato/potato psyllid. Other methods of transmission are also to be investigated including grafting, seed transmission and whether the bacterium can be transmitted by the vector from infected fruit.

  • What is the plant host range of the bacterium?

Initially this will include investigating a range of solanaceae species

  • Further investigate the relationship between the bacterium and the symptoms observed in glasshouse tomato and capsicum crops

Altogether this is a large amount of research work that will take considerable time to complete. This work has been prioritised and the individual results will be provided to MAFBNZ and Industry as these come to hand. Some quite critical information on the disease's vector and transmission should be available over the next few months.

This work will enable MAFBNZ to develop options for managing the disease and will help determine what actions growers can take to protect their crops. There are still a number of other questions to be addressed and MAFBNZ will work closely with, and provide technical support to, a Crown Research Institute and industry funded research programme.

Surveillance

A country-wide surveillance programme is underway with MAFBNZ (AsureQuality) staff visiting twenty five tomato and capsicum glasshouse sites and some plant propagating nurseries across New Zealand to determine the distribution of the bacterium. The individual results will be made available to growers as these come to hand.